Fix leak of message snapshot buffer when attempting to send an illegal object.

runtime/lib/vmservice.cc

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/bootstrap_natives.h"
 #include "vm/dart_api_impl.h"
 #include "vm/datastream.h"
 #include "vm/exceptions.h"
 #include "vm/flags.h"
 #include "vm/growable_array.h"
 #include "vm/message.h"
 #include "vm/message_handler.h"
 #include "vm/native_entry.h"
 #include "vm/object.h"
 #include "vm/port.h"
 #include "vm/service_event.h"
 #include "vm/service_isolate.h"
 #include "vm/symbols.h"
 
 namespace dart {
 
 DECLARE_FLAG(bool, trace_service);
 
-static uint8_t* allocator(uint8_t* ptr, intptr_t old_size, intptr_t new_size) {
+static uint8_t* malloc_allocator(uint8_t* ptr,
+                                 intptr_t old_size,
+                                 intptr_t new_size) {
   void* new_ptr = realloc(reinterpret_cast<void*>(ptr), new_size);
   return reinterpret_cast<uint8_t*>(new_ptr);
 }
 
+static void malloc_deallocator(uint8_t* ptr) {
+  free(reinterpret_cast<void*>(ptr));
+}
+
 
 #ifndef PRODUCT
 class RegisterRunningIsolatesVisitor : public IsolateVisitor {
  public:
   explicit RegisterRunningIsolatesVisitor(Thread* thread)
       : IsolateVisitor(),
         register_function_(Function::Handle(thread->zone())),
         service_isolate_(thread->isolate()) {
     ASSERT(ServiceIsolate::IsServiceIsolate(Isolate::Current()));
     // Get library.
@@ skipping 49 matching lines @@
   }
   GET_NON_NULL_NATIVE_ARGUMENT(SendPort, sp, arguments->NativeArgAt(0));
   GET_NON_NULL_NATIVE_ARGUMENT(Array, message, arguments->NativeArgAt(1));
 
   // Set the type of the OOB message.
   message.SetAt(0,
                 Smi::Handle(thread->zone(), Smi::New(Message::kServiceOOBMsg)));
 
   // Serialize message.
   uint8_t* data = NULL;
-  MessageWriter writer(&data, &allocator, false);
+  MessageWriter writer(&data, &malloc_allocator, &malloc_deallocator, false);
   writer.WriteMessage(message);
 
   // TODO(turnidge): Throw an exception when the return value is false?
   bool result = PortMap::PostMessage(
       new Message(sp.Id(), data, writer.BytesWritten(), Message::kOOBPriority));
   return Bool::Get(result).raw();
 }
 
 
 DEFINE_NATIVE_ENTRY(VMService_SendRootServiceMessage, 1) {
@@ skipping 356 matching lines @@
     ServiceEvent spawn_event(NULL, ServiceEvent::kIsolateSpawn);
     spawn_event.set_spawn_token(&token);
     spawn_event.set_spawn_error(&String::Cast(result));
     Service::HandleEvent(&spawn_event);
   }
 #endif  // PRODUCT
   return Object::null();
 }
 
 }  // namespace dart